A STRONG earthquake has hit southwestern Japan, bringing down buildings, killing at least nine people and injuring hundreds, as rescuers scramble to find residents feared trapped in rubble. Eight of the dead were from the hardest-hit town of Mashiki, about 15km east of Kumamoto city on the island of Kyushu. The initial 6.5-magnitude quake struck at 9.26pm (10.20pm AEST) at a depth of 11km near Kumamoto city on the island of Kyushu, the Japan Meteorological Agency said. There was no tsunami risk. More than 100 aftershocks strong enough to be felt followed in the same region.